Coating apparatus



Filed A ril 12, 1957 Fig.2

INVENTOR.

oes-er m sro/ve United States Patent COATING APPARATUS Robert H. Stone, Indianapolis,

Electra-Coating Corp., tion of Indiana Ind., assignor to Ransburg Indianapolis, Ind., a corpora- This invention relates to apparatus for treating different surfaces of a plurality of articles and more particularly to an improved article hanger for supporting a plurality of articles and which permits exposing different surfaces of such articles for spray coating.

It has heretofore been proposed to coat on production lines regular-shaped articles such as square or rectangular prisms by moving each of them through a first coating zone where two of the opposite sides of each article are coated after which each article is moved out of the first coating zone, is indexed 90 about a vertical axis, and then moved through a second coating zone where the other two oppositely disposed exterior surfaces of each article are coated.

Such a coating operation is reasonably satisfactory where the articles are of regular shape and only the ex-. terior surfaces need to be coated; however, Where such articles are irregularly shaped or have gaps in them or are made up of a plurality of parts some of which require coatings on both sides and others require coatings on only one side, then the above coating system has proved unsatisfactory. In many instances paint is applied where it is not required and a great deal of overspray results. Also, additional hangers are required for the odd-shaped parts and the parts that require a coating on their inner as well as their outer surfaces. Further, since all parts of one article cannot be mounted on one hanger for coating in such coating systems a great deal of additional manual handling of the articles is required.

One object of the present invention is to provide improved coating apparatus in which a plurality of articles are mounted on an article hanger which permits manipulating the articles on the hanger without removing them for applying a more complete coating to their surfaces. Another object of the present invention is to provide improved coating apparatus in which a plurality of articles are mounted on an article hanger of a conveyor which permits manipulation of the articles so that some of the articles can be coated on both the inner and outer surfaces without being removed from the hanger and at the same time maintaining a uniform distance between all the article surfaces being coated and the spray coating devices. Still another object of the present invention is to provide an improved hanger which permits relative movement between a plurality of supported articles to expose different article surfaces for applying a more complete surface treatment to at least some of the articles. A further object of the present invention is to provide an improved article hanger which is adapted to support a plurality of articles whose surfaces are arranged at the periphery of a square or rectangular prism and which provides indexing means for exposing the various sides successively to a spray device and which also provides that some of the article surfaces may be rotated relative to the other article surfaces for exposing still another surface to a spray device for coating.

In carrying out the invention, in one form there is provided an article hanger for use in coating apparatus 2,952,351 Patented Sept. 13, 1960 and which comprises a main support for supporting a. first article, and an auxiliary support connected to the main support for supporting a second article. The auxiliary support is provided with an indexer for permitting rotation of the auxiliary support to present different surfaces of the second article for coating. The indexer is adapted to be manipulated either manually or mechanically for rotating the auxiliary support.

In accordance with another form of the invention, there is provided a conveyor and an article hanger moved by the conveyor. The hanger comprises a main support for a first article and an auxiliary support connected to said main support for supporting a second article. A main indexer is associated with the main support for permitting rotation of the exposed surfaces of the first and second articles, and an auxiliary indexer is associated with the auxiliary support for permitting rotation of the second article relative to the main support and the first article. A first cam means is provided along the conveyor for engaging the main indexer to rotate the main support for exposing different surfaces of the first article and one surface of the second article for coating. A second cam means is positioned along the conveyor for engaging the auxiliary indexer to rotate the second article relative to the main support and the first article for exposing a different surface of the second article for coating.

In addition to the foregoing objects and features of my invention other objects, features, combinations and innovations will be discernable from the following description of a preferred embodiment thereof which is to be taken in connection with the accompanying drawing.

In the drawing:

Figure 1 is a diagrammatic plan view of coating apparatus in accordance with my invention;

Figure 2 is an isometric view of an article hanger in accordance wtih my invention and which is suitable for use with the coating apparatus of Figure l; and

Figure 3 is a detailed isometric View of a portion of one of the indexing devices shown in Figure 2.

Referring to Figure 1 of the drawing, there is shown a coating system which includes an electrically grounded conveyor, diagrammatically shown at 10 and which may be of the type .shown in US. Patent No. 2,463,422 for moving articles in the direction of the arrow 11 through three coating stations identified as A, B and C.

At coating station A there are provided electrostatic spray coating devices 14 and 15 disposed on opposite sides of the conveyor 10 for coating oppositely disposed article surfaces supported from the conveyor. Spray device 14 is connected to the energized terminal of high voltage source 18 by means of conductor 19. The other terminal of the high voltage source 18 is grounded as shown. Spray device 15 is connected to the energized terminal of high voltage source 22 by means of conductor 23. The other terminal of the high voltage source is also grounded as shown.

Disposed between coating stations A and B is cam bar 25 whose function will be described in greater detail hereafter.

At coating station B there are provided electrostatic spray coating devices 28 and 29 disposed on opposite sides of the conveyor 10 and function similarly to the spray devices 14 and 15. Spray devices 28 and 29 are also connected to the energized terminals of the high voltage sources 18 and 22 respectively as shown.

Disposed between coating stations B and C are cam bars 32 and 33 whose function will be described in greater-detail hereafter.

At coating station C spray coating device 36 is disposed on one side-of the conveyor 10 for coating one or more article surfaces on one side of conveyor 10. Spray -device 36 is connected to the energized terminal of the high voltage source 18 similarly to the spray devices 14 and 28. All the spray devices here described are supplied with liquid coating material in a suitable manner from a source not shown, are maintained at a high electrical potential for example 90 kv. negative, and may be constructed in accordance with US. Patent No. 2,764,712. However; the invention is not limited to the use of electrostatic spray coating devices, and other suitable atomizers may be used without departing from the invention.

An article hanger generally designated as 39 constructed in accordance with the invention and which may be used on the conveyor of the apparatus shown in Figure 1 is shown in Figures 2 and 3. This hanger comprises a main support 40 and an auxiliary support 41.

The main support 40 comprises an indexer 44 which includes a fixed spindle 45 and a member 46 rotatably mounted on the spindle '45. One end of the spindle 45 is connected to the chain of the conveyor 10 for move ment thereby or, where it is not used with the apparatus shown in Figure 1, it may be connected to any suitable fixture. The opposite end of the spindle 45 is provided with cam member 47a. The rotatable member 46 comprises cam member 47b, four-pronged wheel 48 and hook portion 49. The cam surfaces on the cam members 4711 and 47b are so formed that the member 46 may be rotated about the axis of the spindle 45 to four stable positions spaced 90 apart.

Supported from thehook portion 49 is a vertical member 50. At the lower end of the member 50 there is rigidly affixed in a horizontal position a U-shaped article carrier 52 which, as shown in Figure 2, supports a 3- sided washer casing 53. This washer casing is maintained on the carrier 52 by pins 54.

Also rigidly connected to the main support 40 by means of a horizontal bar 56 is an indexing device 57. This indexing device comprises a fixed spindle 58 and a hook member 59 rotatably mounted on the spindle 58. The member 59 is provided with a four-pronged wheel 60. Both of members 58 and 59 are constructed like the spindle 45 and the rotatable member 46 respectively of the indexer 44 the details of which have already been described and will not be repeated here.

Article support 62 in the form of a rectangular frame with a cross member 63 is supported from the hook 59 by means of loop 64. Loops 65 and 66 are provided on the upper portion of the frame 62 for supporting article 67 which is a cover for a washer. Loops 68 and 69 are provided on cross member 63 for supporting article 70 which is also a cover for a washer.

In operation the loaded hanger 39 just described is supported on the conveyor and moved by the conveyor 10 through coating zones A, B and C. With the hanger 39 oriented as shown at station A a spray coating is applied to the article surfaces 53a and 530 by the spray devices =14 and 15.

After the spray coating operation at station A is completed, the hanger 39 is moved from station A and past cam bar 25 which engages one prong of the wheel 48 for rotating the hanger 90 about the axis of spindle 45 in the direction of the arrows 72. In its reoriented position the hanger moves into station B where the article surfaces 53b, 67a, :and 70a are spray coated by the de vices 28 and 29.

After the spray coating operation at station B is completed, the hanger 39 is moved from station B and past cam bars 32 and 33 which successively engage two of the prongs on the wheel 60 for rotating the articles 67 and 70 180 about the axis of the spindle 58 in the direction of the arrows 73 and relative to the main support 40 and the article 53. The hanger 39 is then moved to station C where the article surfaces 67b and 70b are exposed to receive a spray coating from the device 36. After the completion of the coating at station C the articles are then moved on for further processing, suchas drying.

While the coating system illustrated in Figure 1 shows mechanical means for rotating indexing devices 44 and 57, it will be readily understood that an operator could manually rotate the rotatable member of either indexer for appropriately orienting the article surfaces for coating.

I claim:

1. An article hanger comprising a main support means for supporting a first article, shaft means on said main support means including means for connecting it to a conveyor for rotation about the axis of the shaft means, said support means having provisions for supporting the first article in fixed angular relation to the support means for rotation therewith, auxiliary support means rigidly connected to said main support means for joint rotation with the main support means and the first article about the axis of the shaft means, said auxiliary support means including a spindle the axis of which is generally parallel to the axis of said shaft means and offset therefrom, and a member mounted on said spindle for rotation about its axis for supporting a second article adjacent the first article and partially shielded thereby, said rotatable member being adapted to be rotated to a different angular position relative to said main support means and the first article for exposing the shielded surface portion of the secondarticle for surface treatment.

2. An article hanger comprising a main support for supporting a first article on a main axis, an auxiliary support rigidly connected to said main support for supporting a second article on a second axis generally parallel to the main axis and offset therefrom, a main indexer means connected to said main support and including a member adapted to be rotated about the main axis for exposing different surfaces of the first and second articles to a spray of coating material, and an auxiliary indexer means connected to said auxiliary support and including a member adapted to be rotated about the second axis and relative to said main support and the first article for presenting a different surface of the second article to a spray of coating material.

3. A hanger comprising a rotatable frame structure for supporting a first article on a main axis, said article comprising a housing with an opening therein, an auxiliary support rigidly connected to said frame structure, said auxiliary support means including an indexer the axis of which is generally parallel to the main axis and offset therefrom for independently supporting a second article on the indexer axis and in the opening of the first article, means on said indexer adapted to be rotated about the indexer axis for orienting the second article to a plurality of different angular positions relative to the first article, and means on said indexer for securing the second article in each of said different angular positions.

4. Article coating apparatus comprising a conveyor, a hanger rotatably supported on said conveyor, a main support rigidly connected to said hanger for supporting a first article on the axis of said hanger, an auxiliary support rigidly connected to said hanger, said auxiliary support including a spindle the axis of which is generally parallel to the axis of the hanger and offset therefrom and a member rotatably mounted on said spindle for supporting a second article on the axis of said spindle and adjacent the first article and partially shielded thereby, means positioned along said conveyor for engaging said rotatable member to rotate it about the axis of said spindle and relative to said main support and the first article for exposing the shielded surface of the second article for coating.

5. Article coating apparatus comprising a conveyor; an indexer support including a main spindle connected to said conveyor and a main support means for supporting a first article, said main support means being mounted on said main spindle for rotation about its axis; an auxiliary indexer support including an auxiliary spindle connected to said main spindle whereby the axis of the auxiliary spindle is generally parallel to said main spindle and offset therefrom, and an auxiliary support means for supporting a second article, said auxiliary support means being mounted on said auxiliary spindle for rotation about its axis; first means positioned along said conveyor for engaging said main support means to rotate it about the axis of said main spindle for exposing difierent surfaces of the first article and a surface 'of the second article for coating; and a second means positioned along said conveyor for engaging said auxiliary support means to rotate it relative to the first article for exposing a different surface of the second article for coating.

6. Article coating apparatus comprising a conveyor, a main article hanger connected to said conveyor, a main support for supporting a first article, said main support being mounted on said main hanger for rotation about its axis, an auxiliary hanger connected to said main support whereby the axis of the auxiliary hanger is generally parallel to the axis of the main hanger and oifset therefrom, an auxiliary support for supporting a second article adjacent said first article whereby a surface portion of the second article is shielded by the first article, said auxiliary support being mounted on said auxiliary hanger for rotation about its axis and relative to the first article, and means positioned along said conveyor for engaging said main support to rotate it about the main hanger axis for presenting exposed surface portions of the first and second articles for coating, said second article being thereafter adapted to be rotated about the axis of said auxiliary hanger for exposing the shielded surface portion of the second article for coating.

References Cited in the file of this: patent UNITED STATES PATENTS 1,219,591 Schmidt Mar. 20, 1917 2,725,034 Philp Nov. 29, 1955 2,769,728 Juvinall Nov. 6, 1956 

